1 files changed, 45 insertions, 6 deletions

diff --git a/miscutils/ubi_tools.c b/miscutils/ubi_tools.c
index dd99a44f4..6f20f300c 100644
--- a/miscutils/ubi_tools.c
+++ b/miscutils/ubi_tools.c
@@ -95,10 +95,11 @@
 //usage:     "\n        -d UBI_NUM      UBI device number"
 //usage:
 //usage:#define ubimkvol_trivial_usage
-//usage:       "UBI_DEVICE -N NAME -s SIZE"
+//usage:       "UBI_DEVICE -N NAME [-s SIZE | -m]"
 //usage:#define ubimkvol_full_usage "\n\n"
 //usage:       "Create UBI volume\n"
 //usage:     "\n        -a ALIGNMENT    Volume alignment (default 1)"
+//usage:     "\n        -m              Set volume size to maximum available"
 //usage:     "\n        -n VOLID        Volume ID, if not specified, it"
 //usage:     "\n                        will be assigned automatically"
 //usage:     "\n        -N NAME         Volume name"
@@ -141,11 +142,19 @@ int ubi_tools_main(int argc UNUSED_PARAM, char **argv)
         int alignment = 1;
         char *type = NULL;
 
-        opt_complementary = "-1:m+:d+:n+:s+:a+";
-        opts = getopt32(argv, "m:d:n:N:s:a:t::",
-                        &mtd_num, &dev_num, &vol_id,
-                        &vol_name, &size_bytes, &alignment, &type
-        );
+        if (do_mkvol) {
+                opt_complementary = "-1:d+:n+:s+:a+";
+                opts = getopt32(argv, "md:n:N:s:a:t::",
+                                &dev_num, &vol_id,
+                                &vol_name, &size_bytes, &alignment, &type
+                        );
+        } else {
+                opt_complementary = "-1:m+:d+:n+:s+:a+";
+                opts = getopt32(argv, "m:d:n:N:s:a:t::",
+                                &mtd_num, &dev_num, &vol_id,
+                                &vol_name, &size_bytes, &alignment, &type
+                );
+        }
         ubi_ctrl = argv[optind];
 
         fd = xopen(ubi_ctrl, O_RDWR);
@@ -173,6 +182,36 @@ int ubi_tools_main(int argc UNUSED_PARAM, char **argv)
         if (do_mkvol) {
                 struct ubi_mkvol_req req;
                 int vol_name_len;
+                if (opts & OPTION_M) {
+                        unsigned leb_avail;
+                        unsigned leb_size;
+                        unsigned num;
+                        char path[sizeof("/sys/class/ubi/ubi%d/avail_eraseblocks") + sizeof(int)*3];
+                        char *p;
+                        char buf[20];
+
+                        if (strncmp(ubi_ctrl, "/dev/ubi", 8) != 0)
+                                bb_error_msg_and_die("%s device node not in correct format", "UBI");
+                        num = xstrtou(ubi_ctrl+8, 10);
+                        p = path + sprintf(path, "/sys/class/ubi/ubi%d/", num);
+
+                        strcpy(p, "avail_eraseblocks");
+                        if ((num = open_read_close(path, buf, sizeof(buf))) <= 1)
+                                bb_error_msg_and_die("%s could not get LEB available", "UBI");
+                        buf[num-1] = '\0'; // trim trailing newline
+                        leb_avail = xstrtou(buf, 10);
+
+                        strcpy(p, "eraseblock_size");
+                        if ((num = open_read_close(path, buf, sizeof(buf))) <= 0)
+                                bb_error_msg_and_die("%s could not get LEB size", "UBI");
+                        buf[num-1] = '\0'; // trim trailing newline
+                        leb_size = xstrtou(buf, 10);
+
+                        size_bytes = leb_avail * leb_size;
+
+                        if (size_bytes <= 0)
+                                bb_error_msg_and_die("%s invalid maximum size calculated", "UBI");
+                } else
                 if (!(opts & OPTION_s))
                         bb_error_msg_and_die("%s size not specified", "UBI");
                 if (!(opts & OPTION_N))